This invention relates to electrical switching apparatus. More particularly, it is concerned with electromagnetically operated switching apparatus employing convertible contact modules which operate in either a normally open or a normally closed condition depending upon their mounting position.
Electrical switching apparatus such as electromagnetic contactors or relays for opening and closing a plurality of switches are well-known. In order to provide versitility contactors of this general type frequently employ switch or contact modules which selectively may be changed to function in either the normally open or normally closed condition. Certain contactors are designed to employ convertible contact modules which when placed in the contactor in one position provide a normally open switch and when removed and replaced in a different position, typically inverted, provide a normally closed switch.
It is desirable to be able to determine by visual observation the mounting positions and consequently the contact conditions of each of the convertible contact modules. Each convertible contact module generally contains indicia in the form of symbols and/or color coding to provide visual indication at a glance as to the position of the convertible contact module. Direct viewing of the indicia on the convertible contact modules may be difficult, however, if a cover or other portion of the apparatus obscures the contact modules. Viewing of the indicia is even more difficult with contactors employing two sets of convertible contact modules with a first set at a lower level and a second set at a second level overlying and obscuring the first set. Contactors of this general type are shown and described in the aforementioned applications.